Engine

Previous studies examining gasoline and hydrogen engines have typically focused on factors pertaining to air to fuel ratios, their effects on an ICE performance, combustion by-products produced during the ignition cycle and its subsequent environmental effects. Alternatively, this study examines the ways in which a hydrogen engine cavitation can be enhanced by using a graphene coated layer on the cylinder combustion chamber walls. SEM micrographs for the coated surfaces' microstructure showed a uniform distribution of the graphene layer that was free from cavities and demonstrating little to no observable defects. The study's results also showed large improvements in the BTE and exhaust temperature with respect to BMEP performance. This further resulted in significantly low levels harmful gaseous emissions, with observable reductions in the emissions of CO, NOx, and hydrocarbon derived from gasoline and pure hydrogen fuel. These results are thus indicative of a significant improvement in the performance of this particular typology of engine, in contrast to other experimentation focus found in other studies.

Fuel conversion efficiency is one of the main concerns in the field of internal combustion engine systems. Although the Otto cycle delivers the maximum efficiency possible in theory, the kinematics of the slider–crank mechanism of the conventional internal combustion engines makes it difficult to reach this level of efficiency in practice. This study proposes using the unique hypocycloid gear mechanism instead of the conventional slider–crank mechanism for the internal combustion engines to increase engine efficiency and minimize frictional power losses. The hypocycloid gear mechanism engine’s kinematics provides the means for the piston-rod assembly to reciprocate in a straight-line motion along the cylinder axis besides achieving a nonlinear rate of piston movement. As a result, this characteristic allows for a true constant-volume combustion, which in turn would lead to higher work output. An in-cylinder gas volume change model of the hypocycloid gear mechanism engine was develop...

The environmental pollution in the metropolitan cities is increasing rapidly mostly because of the increased number of fossil fuel powered vehicles. Many alternative options are now being studied throughout the world. One of the alternative solutions can be a compressed air powered vehicle. The present study focuses on converting an SI engine into a compressed air engine. A two stroke single cylinder SI engine is converted to operate using compressed air because of its design simplicity. The cylinder head of the engine is modified by replacing the existing cam with a set of newly designed flank cam and an inlet-exhaust air passage. As the cylinder head of the engine is modified, the engine is tested for different timing of the valve opening and duration of opening. Three sets of valve timing are used to test the converted compressed air engine. The air pressure used in the present study is 7 bar which is obtained using a compressor. The design and experimental test result presented here can be used for further research and modification of the technique.

In the 21st century, automobile industries are increasing at an unimaginable space. A huge problem of internal combustion (IC) engines is that it is a main cause of noise pollution. That is the reason mufflers are used to reduce the noise produced. Though mufflers are not designed to serve any primary exhaust function, they are installed within the exhaust system of most IC engines. It is designed as a soundproofing device that reduces the loudness of the pressure created by the engine. But mufflers need design and geometry considering the physics behind it which is very confounded. Established muffler design has been an iterative process by trial and error method. With recent research in this area has made it possible to do it in an analytical and experimental way.
There are two types of muffler, absorption type muffler and reactive muffler. The project dealt with the complexity behind the different mufflers and finally designed and constructed an absorption type muffler. After constructing the muffler according to our design using mild steel sheet and steel wool, we compared its performance based on three cases, no muffler condition, laboratory muffler condition and our newly designed muffler condition. Each case we calculated the insertion loss, brake specific fuel consumption (BSFC) and specific fuel consumption (SFC). And finally we showed with graphical representation that, our designed muffler performed better than the laboratory muffler condition and no muffler condition.
Of course, we did not achieve our desired result, since mild steel is no longer used as the construction material anymore and the available steel wool was not quality as we expected. However, we hope using better construction material and our design will certainly reduce the sound pressure level a great deal.

An engine basically is defined as a device which converts chemical energy of the fuel into heat energy and further into mechanical output. Based on classifications there are variety of engines based on the size, position of piston, and farther classification, consideration of various parameters is important so as for the efficient working of an engine. One of them being the heat dissipation. Heat dissipation is an important factor because overheating the engine may not just only reduce its overall performance but may develop thermal stresses, fatigue and over all reduce in the working life cycle of an engine. The paper tries to investigate the thermal distribution of a v8 turbo charge engine block and tries to analyze the cooling effect of air by CFD

Pulse detonation is a propulsion technology that involves detonation of fuel to produce thrust more efficiently than current engine systems. By literature survey and library research it is shown that Pulse Detonation Engine (PDE) technology is more efficient than current engine types by virtue of its mechanical simplicity and thermodynamic efficiency. As the PDE produces a higher specific thrust than comparable ramjet, scramjet engines at speeds of up to approximately Mach 2.3 to Mach 5, it is suitable for use as part of a multi-stage propulsion system. The PDE can provide static thrust for a ramjet or scramjet engine, or operate in combination with turbofan systems. As such, it sees potential applications in many sectors of the aerospace, aeronautic, and military industries. However, there remain engineering challenges that must be overcome before the PDE can see practical use. Current methods for initiating the detonation process need refinement. To this end, many government research bodies and a few private organizations around the world are working on PDS research & further development.

The combustion of fuel inside the internal combustion engine lead to form many by-products like CO2, CO, Exhaust hydrocarbons, various oxides of nitrogen and compound like soot basically known as carboneous deposits. To sustain the engine performance and emission control, this soot must be clean out. This literature contains various mechanical and chemical methods for carbon deposits cleaning, also the formation and adverse effect of soot formation on internal combustion engine. The conventional methods show their performance appreciably on various parameters, but still there is need of a cleaning system that can vanish out all the battle-necks of conventional methods. This literature will also give review about the automated system which will overcome all the drawbacks of conventional methods.

Heuristic methods have been a successful tool for optimizing engine parameters in both simulation and experimental testing. An improved hybrid method applying both the particle swarm optimization method and genetic algorithm was developed, tested, and compared with a basic particle swarm method for improving engine emissions and performance. A computational comparison between the particle swarm optimization–genetic algorithm hybrid, basic particle swarm optimization, and basic genetic algorithm was done using standard test problems. Computational results indicated improvements in both the efficiency and effectiveness of the present hybrid method. Engine testing was performed under steady-state conditions at 1400 r/min at 4.15 bar brake mean effective pressure. The basic particle swarm optimization and the hybrid particle swarm optimization–genetic algorithm method were applied to the test apparatus and used to locate the optimum neighborhood of the engine operation. A single-objecti...

This paper presents experimental results of a new compressed natural gas direct injection (CNG-DI) engine that has been developed from modification of a multi cylinder gasoline port injection (PI) engine. The original gasoline-PI engine was also modified to a CNG bi-fuel system. The test results obtained from CNG fuel using two different systems (i.e. bi-fuel and DI) have been investigated and compared with the original gasoline engine. The objective of this investigation is to compare the test results between CNG-DI, with CNG-BI and gasoline-PI engines with the same displacement volume. It was found that the CNG-DI engine produces similar brake power at 6000. rpm and wide open throttle (WOT) but produces higher brake power at part load condition as compared to the original gasoline. The CNG-BI engine produces 23% lower brake power than the CNG-DI engine. The average brake specific fuel consumption (BSFC) of the CNG-DI engine was 0.28% and 8% lower than gasoline-PI and CNG-BI engines respectively. The CNG-DI engine reduces 42% NOx emission as compared to the base engine. However, the CNG-DI engine produces higher HC and CO emissions as compared to the base engine. This paper discusses a review on the direct injection (DI) natural gas engine with new information along with other investigations. © 2011 Elsevier Ltd.
http://ac.els-cdn.com/S0360544211002349/1-s2.0-S0360544211002349-main.pdf?_tid=c2bf5f32-a9c6-11e3-b389-00000aab0f01&acdnat=1394615868_af9452d9cda4f71e98e5cd80760b3339 
http://www.sciencedirect.com/science/article/pii/S0360544211002349

The name itself shows that this engine is a cycle of six strokes where two strokes are the power strokes. This is additionally a reciprocating sort of engine with twofold progression of charge and it very well may be both internal and external ignition. It totally differ with the 2 stroke and 4 stroke engine because of its thermodynamic cycle. This type of engine consist of a “modified cylinder head” with “with two supplementary chambers” one is combustion chamber and the other one is an air heating chamber and both the chambers are totally independent from the cylinder. The design analysis of this type of engine is quite easy because of separated cylinder and combustion chamber. In this type of engine two valves are added with comparison of four stroke engine and both the valves are operated by an arrangement of piston. This engine is more efficient thermodynamically because the volume change in power stroke is more than the compression stroke and intake stroke. The leading advantage of this engine is “the reduction in fuel consumption by 40%”, there are two power stroke in the cycle of six strokes, and it is also less polluting type of engine. Six stroke engine's selection by the vehicle industry would tremendously affect the earth and world economy.